Polyoxometalate Complexes as Precursors to Vanadium‐Doped Molybdenum or Tungsten Oxide Thin Films by Means of Aerosol‐Assisted Chemical Vapour Deposition

Aerosol‐assisted chemical vapour deposition of substituted polyoxometalates H 4 [PMo 11 VO 40 ], H 7 [PMo 8 V 4 O 40 ], [ n Bu 4 N] 4 [PVW 11 O 40 ] and [ n Bu 4 N] 5 [PV 2 W 10 O 40 ] resulted in the formation of vanadium‐doped metal oxide thin films. Depositions were carried out at 550 °C in methanol or acetonitrile for the POMs that contained molybdenum or tungsten, respectively. The as‐deposited films were X‐ray amorphous and relatively non‐adherent. However, on annealing in air at 600 °C, decolourised translucent films that were more mechanically robust were obtained. Films deposited from H 4 [PMo 11 VO 40 ] and H 7 [PMo 8 V 4 O 40 ] consisted of V‐doped MoO 3 in the orthorhombic phase and films from [ n Bu 4 N] 4 [PVW 11 O 40 ] and [ n Bu 4 N] 5 [PV 2 W 10 O 40 ] comprised of monoclinic V‐doped WO 3 . All films were fully characterised by using X‐ray photoelectron spectroscopy, energy‐dispersive X‐ray diffraction, scanning electron microscopy and UV/Vis spectroscopy.